Source Code for Module pyjamas.ui.Widget

  1  # Copyright 2006 James Tauber and contributors 
  2  # Copyright (C) 2009 Luke Kenneth Casson Leighton <lkcl@lkcl.net> 
  3  # 
  4  # Licensed under the Apache License, Version 2.0 (the "License"); 
  5  # you may not use this file except in compliance with the License. 
  6  # You may obtain a copy of the License at 
  7  # 
  8  #     http://www.apache.org/licenses/LICENSE-2.0 
  9  # 
 10  # Unless required by applicable law or agreed to in writing, software 
 11  # distributed under the License is distributed on an "AS IS" BASIS, 
 12  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
 13  # See the License for the specific language governing permissions and 
 14  # limitations under the License. 
 15  from pyjamas import DOM 
 16  from pyjamas import Factory 
 17  from pyjamas import log 
 18   
 19  from UIObject import UIObject 
 20  from pyjamas.ui import Event 
 21  from ClickListener import ClickHandler 
 22  from FocusListener import FocusHandler 
 23  from KeyboardListener import KeyboardHandler 
 24  from MouseListener import MouseHandler 
 25   
 26 -class Widget(UIObject): 
 27      """ 
 28          Base class for most of the UI classes.  This class provides basic services 
 29          used by any Widget, including management of parents and adding/removing the 
 30          event handler association with the DOM. 
 31      """ 
 32 -    def __init__(self, **kwargs): 
 33          self.attached = False 
 34          self.parent = None 
 35          self.layoutData = None 
 36          self.contextMenu = None 
 37   
 38          UIObject.__init__(self, **kwargs) 
 39   
 40 -    def getLayoutData(self): 
 41          return self.layoutData 
 42   
 43 -    def getParent(self): 
 44          """Widgets are kept in a hierarchy, and widgets that have been added to a panel 
 45          will have a parent widget that contains them.  This retrieves the containing 
 46          widget for this widget.""" 
 47          return self.parent 
 48   
 49 -    def isAttached(self): 
 50          """Return whether or not this widget has been attached to the document.""" 
 51          return self.attached 
 52   
 53 -    def setContextMenu(self, menu): 
 54          self.contextMenu = menu 
 55          if menu: 
 56              self.sinkEvents(Event.ONCONTEXTMENU) 
 57          else: 
 58              self.unsinkEvents(Event.ONCONTEXTMENU) 
 59   
 60 -    def onBrowserEvent(self, event): 
 61   
 62          # farm out the event to convenience handlers. 
 63          # detect existence by checking for the listener lists of each 
 64          # type of handler.  there's probably a better way to do this... 
 65          if hasattr(self, "_clickListeners"): 
 66              ClickHandler.onBrowserEvent(self, event) 
 67          if hasattr(self, "_keyboardListeners"): 
 68              KeyboardHandler.onBrowserEvent(self, event) 
 69          if hasattr(self, "_mouseListeners"): 
 70              MouseHandler.onBrowserEvent(self, event) 
 71          if hasattr(self, "_focusListeners"): 
 72              FocusHandler.onBrowserEvent(self, event) 
 73   
 74          if self.contextMenu is None: 
 75              return True 
 76   
 77          type = DOM.eventGetType(event) 
 78          if type == "contextmenu": 
 79              DOM.eventCancelBubble(event, True) 
 80              DOM.eventPreventDefault(event) 
 81              self.contextMenu.onContextMenu(self) 
 82              return False 
 83   
 84          return True 
 85   
 86 -    def onLoad(self): 
 87          pass 
 88   
 89 -    def doDetachChildren(self): 
 90          pass 
 91   
 92 -    def doAttachChildren(self): 
 93          pass 
 94   
 95 -    def onAttach(self): 
 96          """Called when this widget has an element, and that element is on the document's 
 97          DOM tree, and we have a parent widget.""" 
 98          if self.isAttached(): 
 99              return 
100          self.attached = True 
101          DOM.setEventListener(self.getElement(), self) 
102          self.doAttachChildren() 
103          self.onLoad() 
104   
105 -    def onDetach(self): 
106          """Called when this widget is being removed from the DOM tree of the document.""" 
107          if not self.isAttached(): 
108              return 
109          self.doDetachChildren() 
110          self.attached = False 
111          DOM.setEventListener(self.getElement(), None) 
112   
113 -    def setLayoutData(self, layoutData): 
114          self.layoutData = layoutData 
115   
116 -    def setParent(self, parent): 
117          """Update the parent attribute.  If the parent is currently attached to the DOM this 
118          assumes we are being attached also and calls onAttach().""" 
119          oldparent = self.parent 
120          self.parent = parent 
121          if parent is None: 
122              if oldparent is not None and oldparent.attached: 
123                  self.onDetach() 
124          elif parent.attached: 
125              self.onAttach() 
126   
127 -    def removeFromParent(self): 
128          """Remove ourself from our parent.  The parent widget will call setParent(None) on 
129          us automatically""" 
130          if hasattr(self.parent, "remove"): 
131              self.parent.remove(self) 
132   
133 -    def getID(self): 
134          """Get the id attribute of the associated DOM element.""" 
135          return DOM.getAttribute(self.getElement(), "id") 
136   
137 -    def setID(self, id): 
138          """Set the id attribute of the associated DOM element.""" 
139          DOM.setAttribute(self.getElement(), "id", id) 
140   
141  Factory.registerClass('pyjamas.ui.Widget', Widget) 
142